<nb-layout>
  <nb-layout-header fixed>
    <button nbButton status="success" size="xsmall" (click)="toggle()">Toggle</button>
  </nb-layout-header>
  <nb-sidebar fixed></nb-sidebar>

  <nb-layout-column>Long layout content so that it is clear that fixed sidebar is shown on top of the content.</nb-layout-column>
</nb-layout>
